Central air conditioning systems rely on ducts to distribute conditioned air throughout your home. While this may seem practical, ductwork can present various issues. For example, holes, poor connections, and leaks are common. According to EnergyStar.gov, these often result in the loss of 20% to 30% of conditioned air in a house.1 However, duct sealing can resolve this and other problems associated with poorly performing ducts.
Signs of Poorly Sealed Ducts
Leaks in your ductwork can have various impacts. These can include:
- Higher utility bills in the summer and winter.
- Difficulty heating or cooling rooms in your home.
- Rooms that never feel comfortable or are downright stuffy.
- Higher humidity, caused by moisture leakage into ducts.
- Musty odors from vents or visible mold near vents/registers.
- Signs that rodents have chewed their way into a flexible duct.
You can assess the potential for leaky air ducts by inspecting their general condition or looking where they are located. If flexible ducts are kinked or tangled, there may be an air leak or at the very least restrictions in air flow. Ducts in the garage, crawlspace, or attic are most at risk of leaks and efficiency issues.
How Duct Sealing Works
Traditionally, ductwork is sealed by applying tape, mastic, or insulation. A strip of foil tape can be used to seal off seams along straight runs. At elbow joints, duct mastic can be applied using a paintbrush. Installing foil-faced fiberglass insulation requires measuring the circumference of the duct and cutting the material to size, wrapping it around the duct, and applying foil tape to close the seam.
Pre-formed duct insulation can also be purchased. Installing it requires disconnecting an elbow. On the exposed duct end, a plastic cap is snapped on to secure the insulation and prevent it from snagging. The pre-formed piece can then be fit over the duct and pulled over its entire length.
While DIY methods can be effective, adhesive tape can break. Applying a silicone-based duct sealant can effectively cover cracks and holes, but can be tricky. Even if the tape covering it may fall off, the sealant should remain in place. However, contractors offer a more effective, lasting solution by sealing ductwork from the inside.
Professional Duct Sealing
Once a contractor has inspected the ductwork, repaired or replaced sections as needed, and tightened loose sections, they’ll use a state-of-the-art method to seal ducts from the inside. This requires removing the supply and return register grilles. Next, these openings are closed off and the contractor can now pressurize the duct system using a blower fan. Air leakage is analyzed using a computer.
Once air leakage is accurately measured, the technician will blow a liquid-rubber sealant mist into the system. When introduced into ducts, it automatically seals holes, cracks, and seams. Air should stop leaking once these are plugged up. After the process is complete, a second pressurized blower test will be performed to measure whether any air leakage is still occurring.
A professional can also insulate ducts in unconditioned spaces, add a new filter, and conduct safety tests. They’ll determine if gas-burning appliances are releasing byproducts such as carbon monoxide. An air flow evaluation will also be done to identify any HVAC performance and efficiency issues. The contractor will make sure all issues present are fully resolved.
IRBIS’s Air Duct Professionals Can Help
Duct sealing can improve comfort, indoor air quality, and safety as well as save both energy and money. At IRBIS, we are experts in duct repair and replacement. All services start with a thorough inspection; our team can then correct any issues present. To learn more about our air duct services and book a visit, get in touch with us online or call 669-266-5464.